The Total Number of Websites on Earth

A Netcraft report suggests that the total count of websites (including blogs ?) is around 156 million.

Since the Netcraft chart says "hostnames", I guess the numbers include blogs as well that are hosted on subdomains of Blogspot, Twitter, TypePad, Windows Live Spaces or WordPress.com.

Now Technorati claims that the total number of blogs alone is currently in excess of 100 million while Netcraft puts Blogs+Websites = 156 million so there’s probably a mismatch somewhere. Anyone got clues ?